Steph, first up CONGRATULATIONS! way to go, girl!
then, (and i address this to everyone), note that a large part of this has to be that you already had the affection and respect of the people that you work with, and this, rather than some organisational policy, smoothed the way.
which is a lesson to us all ... if everybody hates you as a rat, becoming a female rat won't do much more than make you more vulnerable ... but if they like you as a decent person, becoming a female person is just an opportunity to celebrate a strong community's linkages, and enhances the quality of that workplace for all.
so as one who appreciates your obvious quality, i celebrate joyously with you!